Flexible inorganic double helix material can be adapted to a wide range of applications

Needles of the flexible semiconducting material SnIP; on the left side residual black phosphorus and tiniodide (red) – Photo: Andreas Battenberg / TUM

A flexible semiconductor for electronics, solar technology and photo catalysis

It is the double helix, with its stable and flexible structure of genetic information, that made life on Earth possible in the first place. Now a team from the Technical University of Munich (TUM) has discovered a double helix structure in an inorganic material. The material comprising tin, iodine and phosphorus is a semiconductor with extraordinary optical and electronic properties, as well as extreme mechanical flexibility.

Flexible yet robust – this is one reason why nature codes genetic information in the form of a double helix. Scientists at TU Munich have now discovered an inorganic substance whose elements are arranged in the form of a double helix.

The substance called SnIP, comprising the elements tin (Sn), iodine (I) and phosphorus (P), is a semiconductor. However, unlike conventional inorganic semiconducting materials, it is highly flexible. The centimeter-long fibers can be arbitrarily bent without breaking.

“This property of SnIP is clearly attributable to the double helix,” says Daniela Pfister, who discovered the material and works as a researcher in the work group of Tom Nilges, Professor for Synthesis and Characterization of Innovative Materials at TU Munich. “SnIP can be easily produced on a gram scale and is, unlike gallium arsenide, which has similar electronic characteristics, far less toxic.”

COUNTLESS APPLICATION POSSIBILITIES

The semiconducting properties of SnIP promise a wide range of application opportunities, from energy conversion in solar cells and thermoelectric elements to photocatalysts, sensors and optoelectronic elements. By doping with other elements, the electronic characteristics of the new material can be adapted to a wide range of applications.

Due to the arrangement of atoms in the form of a double helix, the fibers, which are up to a centimeter in length can be easily split into thinner strands. The thinnest fibers to date comprise only five double helix strands and are only a few nanometers thick. That opens the door also to nanoelectronic applications.

JUST AT THE BEGINNING

“Similar to carbon, where we have the three-dimensional (3D) diamond, the two dimensional graphene and the one dimensional nanotubes,” explains Professor Nilges, “we here have, alongside the 3D semiconducting material silicon and the 2D material phosphorene, for the first time a one dimensional material – with perspectives that are every bit as exciting as carbon nanotubes.”

Just as with carbon nanotubes and polymer-based printing inks, SnIP double helices can be suspended in solvents like toluene. In this way, thin layers can be produced easily and cost-effectively. “But we are only at the very beginning of the materials development stage,” says Daniela Pfister. “Every single process step still needs to be worked out.”

Since the double helix strands of SnIP come in left and right-handed variants, materials that comprise only one of the two should display special optical characteristics. This makes them highly interesting for optoelectronics applications. But, so far there is no technology available for separating the two variants.

Theoretical calculations by the researchers have shown that a whole range of further elements should form these kinds of inorganic double helices. Extensive patent protection is pending. The researchers are now working intensively on finding suitable production processes for further materials.

The Latest on: Inorganic double helix

November 20, 2016 - He is a 2010 graduate of Virginia Military Institute and is employed by Helix Electric, Inc. The bride was escorted down the aisle by her father, Raymond. The matron of honor was Mrs. .... The bride's parents hosted a reception on Saturday, May 14 ...

September 13, 2016 - “This property of SnIP is clearly attributable to the double helix,” says Daniela Pfister, who discovered the material and works as a researcher in the work group of Tom Nilges, Professor for Synthesis and Characterization of Innovative Materials at TU ...

September 12, 2016 - It is the double helix, with its stable and flexible structure of genetic information, that made life on Earth possible in the first place. Now a team from the Technical University of Munich (TUM) has discovered a double helix structure in an inorganic ...

September 12, 2016 - Researchers at Drexel University (Pennsylvania) and the Korea Institute of Science and Technology have discovered a cost-effective and efficient way to shield electronic components and enclosures using a spray-compatible coating only a few micrometres ...

September 9, 2016 - Scientists at the Energy Department's National Renewable Energy Laboratory (NREL) discovered a use for perovskites that runs counter to the intended usage of the hybrid organic-inorganic material.

August 16, 2016 - Williams started his chemical career early, as an inorganic chemist. (Organic chemists study carbon, while inorganic chemists study metals.) As an undergraduate, Williams researched how transition metals bind non-metals. His work formed the basis for ...

July 25, 2016 - and eventually some of their RNA mutated into the familiar double helix of genetic information we know as DNA. Those genomes got longer and more complicated, encoding information for the most successful types of RNA and protein ... Chemical reactions ...

February 8, 2016 - "In the biological world, we see inorganic minerals being shaped with remarkable control but until now we haven't understood how it was happening at the level of the atoms," explains Professor Hofer. "Now we see that the organic molecules are acting as ...

August 16, 2012 - While it appears in forms great and small in varied organisms, it is very rare in inorganic chemistry. “So, you can imagine our excitement when, using computer models, we predicted the existence of double-helix structures in simple lithium-phosphorus ...

December 2, 2016 - "In a developed market, you are competing with cheaper forms of conventional power generation, such as gas and also hydro. Energy storage costs still have some way to come down for a hybrid plant like Kennedy Energy Park to be competitive," he said.

December 1, 2016 - SEATTLE - When firefighter paramedics Morlon Malveaux and Mark Pedeferri learned that their powerhorse diesel ambulance was going to be traded for a gas-powered hybrid they were more than a little concerned. The two, who run a Medic One rig ...